Unit Converter
Convert length, weight, and temperature between common units, live as you type.
How this tool works
Pick a category
Length, weight, or temperature.
Choose your units
Select the From and To units from each dropdown.
Enter a value
Type in the From field and the converted result appears immediately.
Swap or adjust as needed
Change either unit at any time and the result recalculates live.
Quick facts
- Category
- Calculators
- Best for
- Converting a recipe or spec sheet between metric and imperial
About this tool
Convert between everyday units across three categories: length (meters, kilometers, miles, feet, inches), weight (kilograms, pounds, ounces, grams), and temperature (Celsius, Fahrenheit, Kelvin), with the result updating live as you type or change either unit dropdown. Length and weight conversions work by converting through a common base unit (meters and grams respectively) using precise standard conversion factors, while temperature uses its own dedicated formulas since Fahrenheit and Celsius scales don’t share a simple multiplicative relationship the way length and weight units do - converting temperature by treating it as a linear scale factor would produce wrong answers. Useful for recipe conversions, travel planning, or converting a spec sheet’s units to whatever system you think in. Runs entirely client-side.
Why use this tool
Three categories, one tool
Length, weight, and temperature all live in the same converter instead of three separate ones.
Precise standard factors
Uses internationally defined conversion factors, not rounded approximations.
Correct temperature math
Temperature uses proper offset formulas instead of treating it as a simple scale factor, which would be wrong.
Live as you type
No convert button - results update immediately as you type or change a unit.
Frequently asked questions
Length and weight units are all direct multiples of each other - a kilometer is always exactly 1000 meters, no matter the value - so converting through a common base unit with a multiplication works cleanly. Celsius and Fahrenheit, by contrast, have different zero points as well as different scale sizes, so converting between them requires an offset in addition to a multiplier (like °F = °C × 9/5 + 32), which is why temperature uses its own dedicated formulas instead of a simple conversion-factor table.
Length and weight use the internationally defined standard conversion factors (for example, exactly 1609.344 meters per mile and exactly 453.59237 grams per pound), so results are accurate to the precision JavaScript’s floating-point math supports - more than sufficient for everyday conversions, though very large numbers can accumulate the same small floating-point rounding any calculator would show.
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